## Summary / 摘要
- Make ChatGPT/Codex built-in `imagegen` the default image path for low
and standard pet creation, requesting genuine transparent PNG source
art.
- Add version 2 `native_alpha` frame jobs that preserve authored Alpha
and visible RGBA, clear only hidden RGB under Alpha 0, keep
source-resolution masters, and perform at most one premultiplied
linear-light downscale.
- Retain version 1 readability and an explicit version 2 `chroma_key`
compatibility path for opaque-only providers; native failures never
silently fall back to chroma.
- Synchronize Studio prompts, Maker/Studio skills, V3 contracts,
architecture/public docs, plugin version 0.5.7, and the unreleased
changelog fragment.
## Validation / 验证
- `./script/validate_pre_push.sh`
- 103 Python pet-production and Skill contract tests
- 42 PetCore `integration_b` tests
- Focused PetCore external-helper prompt contract test
- 5 Portable Maker Skill Swift tests
- Plugin version and changelog policy validators
## Development claim / 开发声明
- Domain: `maker-generation`
- Claim: `maker-skills`
- Base commit: `2844e0803734247f16d3667711479856249d13ae`
- Release preparation: `no`
- Scope note: this is one atomic cross-contract delivery spanning the
Maker skills, Studio generation prompt, durable contracts, public
documentation, and their synchronized version tests.
- Focused validation:
- `cargo test -p petcore --test integration_b --locked`
- `./script/validate_pet_skills.sh`
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Co-authored-by: gd-ops <gd-ops@xmfunny.com>
